This invention relates to a unique structure useable as a spacer and, more particularly, to a spacer structure that is ideally suited for use as a fan stator vane spacer in a gas turbofan engine.
In gas turbofan engines that are commonly used both on civil and military aircraft, the necessary removal of each spacer between every two adjacent stator vanes of the multiple-stage fan results in approximately a seventy percent scrappage of the spacers at overhaul. This is because the present method of assembly is to fair all edges of the spacer using either a "Churchill" or a "JA106A" (or "JA106B") fairing compound to reduce "short circuits" (i.e., deviations) of the fore-to-aft fan air flow around the vane ends and beneath the spacers. Some of these fan stator vane spacers, including those referred to as "mid inner" spacers, are bonded to the fan stator vane ring, which said bonding adds to the difficulty in removing these spacers and adds to the scrappage problem. In addition, these "mid inner" spacers are subject to rotor blade ice impact damage.
I have invented a structure that is generally useable as a spacer; that is also adaptable for use as a mid inner spacer for fan stator vanes; that is releasably attachable to a fan stator vane ring, rather than bondable thereto; that greatly reduces scrapage at overhaul; that eliminates or at least substantially reduces fan air flow "short circuits"; that resists ice impact damage; and, that accomplishes all of the foregoing at a cost less than, or not higher than, the present cost of spacers and their replacement. Thereby, I have significantly advanced the state-of-the-art.